Rocking the Lido this morning at boisterous press screenings, the competition gala bow of Three Billboards was equally met with spontaneous applause and emotional swells. There’s a particular diatribe from lead Frances McDormand that has had all audiences so far in thrall.

Ahead of the gala tonight, McDonagh told me how pleased he was that the darkly comic film seemed to be striking a chord.

The three main stars, McDormand, Woody Harrelson and Sam Rockwell, have all elicited awards buzz with Rockwell a particular breakout. The Confessions Of A Dangerous Mind, Moon and The Way Way Back actor has been called a revelation here for his turn as a mama’s boy racist cop whose eventual arc results in redemption.

Co-financed by Film4, Three Billboards sees McDormand as Mildred Hayes (whom she likened to a grown up Marge Gunderson earlier today) who makes a bold move after her daughter’s murder: She posts a trio of outdoor signs with controversial messages along the road that leads into her small southern town. Her target is William Willoughby (Harrelson), the revered local police chief. When his second-in-command, Officer Dixon (Rockwell), gets involved, the battle between Mildred and Ebbing’s law enforcement becomes highly charged — even as each character’s humanity shines through.

The film next lands in Toronto and then closes the London Film Festival in October ahead of a November 10 U.S. release via Searchlight.